2A+B→2C+D Let order with respect to A and B are x and y respectively. ∴ Rate =k[A]x[B]y 7.2×10−2=k(0.3)x ...(i) 2.88×10−1=k(0.3)x(0.4)y ...(ii) 6×10−3=k(0.1)x(0.1)y ...(iii) 2.4×10−2=k(0.4)x(0.1)y ...(iv) Dividing Eq. (i) by Eq. (ii), we get
7.2×10−2
2.88×10−1
=
(0.2)y
(0.4)3
1
4
=(
1
2
)3 ∵ (
1
2
)z=(
1
2
)y ∴ y = 2 Dividing Eq. (iii) by Eq. (iv), we get